+typedef void (*http_channel_destroy_t)(void *data, struct http_channel *c,
+ void *data2);
+
+http_channel_observer_t http_add_observer(struct http_channel *c, void *data,
+ http_channel_destroy_t);
+void http_observer_set_data2(http_channel_observer_t obs, void *data2);
+
+void http_remove_observer(http_channel_observer_t obs);
+struct http_channel *http_channel_observer_chan(http_channel_observer_t obs);
+#endif
+